Adjustable reamer.



H. WALTHER.

'i .ADJUSTABLE BEAMER. APPLICATION FILED 15511.11, 1908.

. Patented sept. 5, 1911.n

B SHEETS-SHEET l.

H. WALTHER.. ADJUSTABLE BEAMER.A APPLICATION FILED IEB.11,`1908.

Panted sept.f5,' 1911.

^ hmmm `3 SEBBTB-SHEBT 2.

@vlihwsoco u Hi WALTEER- ADJUSTABLE REAMBR; APPLIUA'TION FILED rmml, 1908.

3 BHEETSFSHEET 3.

HENRY WALTHER, 0F MILWAUKEE, WISCOITSIN,

ADJUSTABLE BEAMER.

Specification of Letters Patent.

Application led 1February 11, 1908. Serial No. 415,306.

Patented Sept. 5, 1911.

To all whom 'it may concern:

Be it known that I, HENRY WALTHER, of Milwaukee, Wisconsin, have invented an Adjustable Reamer, of which the following.

is a speciication.\ A

The object of my invention is to provide a'n adjustable expansion reamer of superior simplicity, greater rigidity greater accuracy and ease of adjustment than anythingV heretofore existing.

More particularly I aim to produce a reamer with means for adjust-ing the effec-A tive cutting diameter to any desired bore Y and with a ne degree of adjustment in an improved manner.

In adjusting the cutting diameter of ordinary expansion reamers, it. is necessary -to go' through a cutandtry ,ioperatiom the reamer being expanded orcontraeted to ap prximately the right diameter, than cali-- pered or gaged, and if found still too'larg'fe-v or too small again expanded or contracted slightly and again calipered, and so on until exactly the right diameter is obtained, after which this diameter is lockedy up. Such an operation'is a tedious one and one which requires the tool to be taken to the tool-room or shop to be changed, and more'- over, requires so much time that the `value of the adjustable feature is largely nullified. Furthermore it cannot be carried out on reamers having an-uneven number of blades. In my invention, this `trial and error method is completely eliminated, as is also the calipering. Brieiy,`l provide a means whereby the reamer can be set at once tothe desired diameter' and with micrometricaccuracy, in

the same way as a micrometer gage or caliper is set, that is, by meansvof a graduated screw.. In order to avoid any diiiiculty in having the graduations tit the blades, I; prof vide means T for resetting' the""graduation marks to zero as the cutters are worn down l and require to be reground, to center the 45 blades "1n `the reamer, or when new blades are inserted therein. also such that it admits of absolute rigidity of the cutter-blades with av minimum 'of strain upon the adjusting parts, which strain has been a disadvantageous feature of many reamers. v

A special formof my reamer has been devised and is here shown which iis'capable of being used in the manner of a shell-reamer,

to wit, being tubular and adapted to be placed upon a mandrel for use; but it difand much' vofvc'onstruction which will My arrangement is fers entirely from the so-called shell-ream ers in the fact that it is capable of a much greater range of expansion than the latter-thatis, one measured in inches rather than thousanths of an inch; that the ends of the cutting-blades at all times extend beyond the end ofthe cutterhead, whereby the latter does notinterfere with the former reaching the .bottom of a hole, and that at the same time-the .cutting-blades are at all times supported by resting firmly upon the solid end V.of the cutter-head.

A novel construction embodied in my l reamer consists in making the cutter-head and stock in two pieces united by a separable joint midway of the reamer, and inserting the central core-piece or pieces through ther'openings at the united ends of these features, whereby it becomes possible to make the head-endof the cutter-head solid and to secure certain further peculiarities be hereinafter described.

Vr My 'reamerf has the peculiarity distinit-i'rom others, that the construction is slehvasto permitof the cutter-blades of three or four. For example, no reamer now constructed so far as I am aware 1s small-sized reamer constructed according-toVV i my invention, and Sheet 2 shows alargesized hollow or tubular reamer embodyingthe same principle. Figure 1 is an elevation and Fig. 2a longitudinal section of theaforesaid' small-sized reamer; n3, ,4, 5

and 6 are-transverse sections of the *sameV taken on theplane of the lines 3, 4, 5 and V6 respectively; Fig. 7 is an end view from 4the lower end thereof; Fig. 8 is part `elevalos f y tion andlpart section-.of the adjusting lock/f nut; Figsfisa sidelelevation of the stock shown separately, and in aplane at rightangles tothat of Fig. 2; 'Fig. 10 is part ele- -vation and part section ofthe clamping-nut, ina plane at right-angles to that of Fig.- 2; Fig. lljis a side-elevation ofthe clampingscrew; Figs. 1 2 to y15 inclusive are half sideelevations and-,half sections of theadjustfing-nut, calibrating-` lock-nut, Calibratingsleeve and abutment-sleeve respectively;

` Fig. 16 is a longitudinal section of the cutter-head lshowing alternative forms'of the fcutters, core-block' and clamping-nut; Fig.

17 isl a perspective view ofgthe'cross-bar for v.the core-rod; Figs. 18 and`19 areside elevations of the core-rod andcore-block respectively; Fig. `2Ois 'in part side-.elevation and part` section of the alternative form of Aclzunping-nut shown in Fig. 16; Figs. 21

and 22 are vrespectively an end and side elevation of the alternative form of cutterblades Vshown in Fig. 1 6.l In Sheet 2,the

figures showingthe larger sizedvrgamer are as follows: Fig.Y 23 is a side elevation and `F ig. 24 a longitudinal section, =.the. coreblock, lclamping-nut and clamping-screw in this latter being shown in part elevation; Figs. .25,126,27 and 28 aretransverse sections on the planes represented by thellines 25, 26, 27 and 28 respectively; Fig. 29 isa erspective lview'of one ofthe wing-pleces for the core, showing .a slightly 'modified I form; Fig. '30 is a longitudinal section l.of

a still larger sizedrealner, andV Fig.. 31 is anY end view thereof. l l

In these drawings thesame reference letter and numeral refersfalways to the saine art. A Y

p Referringirst to Sheet 1 of the drawing,

the small sized-reanie'rl comprisesas shown I. nineteen parts, to wit, a main body or stock A (Fig. 9); a1 cutter-head .B (Fig.

'16); five cutter-blades' C; abutment-sleeve D (Fig. 15); clamping-nut E. (Fig. 10)',

rcarrying a pin 'orscrew. F in the side thereof; clampingscrew Gr l1);

core-block -H (Fig. x19); core-rod I (Fig.

18) cross-bar J (F ig.'17); adjusting-'nut K (Fig. 12).; calibratinglsleeve M' (Fig.

14); calibrating lock-nut N (Fig. .-13); adjusting lock-nut 'C (Fig. `8); and a turning-head1?. All the other parts'are mounted on or in the stock A' and cutter-head B, and .it will belobserved' that these two'are connected together at an intermediate pointof the length of the reamer by a separable .serewq'ointformed by a 'A threaded boss a `on the stock and the .in-

teriorthreads b formed in the end of the Abore b2 ofthe cutter-head. In the bore bz l .are slidably mounted the core-block H and ..the 'clamping-nut E, which oppose each other toclamp the blades C in adjusted por sition. These blades 'are set in radial Vslots .b3 inthe cutter-head as shown, being reeupon the ,oblique end-face b5 of the slot b3 ,which-is, 'or ought to be,

parallel to the edge c3. rlfhe oblique face czabuts upon the conical face It of the core-block H, which is or should be formed with the saine angle. The oblique edge c* is undercut and abuts upon the undercut-conicalface e of the clampingn'ut E, -whichis moved up to engage the Each blade, as will be seen, is

same bynieans of the clamping-screw GQ (mounted in the end of the bore b2 and having a square or polygonal head g projecting through a hole bG inthe cutter-head, and having a circular flange gabutting against the end of the bore. The clamping-nut E is keptl from rotating by means of the pin or screw F, which lies in one of the slots b3.,

the inner edge ofA one cutter-blade C being Y.

cut away as shown at 05 to leave room for it. Thev precise angle of Obliquity of the edge c4 and the ,coned face c is not of consequence, and #it may' even be ninety degrees, as illustrated in Figs. 16, 2O and. 22, which will be *described hereinafter.-

I, which is fitted to slide longitudinally in the central bore ofthe stock A. Uponthe upper end of this in turn rests thecross-bar J, which .slides longitudinally inra transverse slot 'a3 in the stock. The diameter of the.` stock at "this point is inade slightIy smallerv than lower down, to enable the ends of the bar. J `t0 project so as to engage the internal annular shoulderk ofthe adjust- ,ing-nut K, which has a set of threads 7a2 engaging corresponding threads afon the largerA vdiameter of thevstock. .It will be seen therefore that the nut K serves to adjust the position of the blades C by advancing the core-block H through the medium of the Upon the core-block HI abuts the end of thecore-rod` rod I and the cross-bar J, and in connection with'gthe clamping-nut E' and clampingscrew G r to secure the'blades in their adjusted position. The nut K is itself'secured in its adjusted-position by 'means of a lock! nut O which engages threads 'a5 on the smaller diameter of the stock A, which threads' are preferably of a slightly diferent locking-action is produced. In Fig. 8 the lock-nut O is shown with reverse or lefthanded threads o', which may be used in y pitch from the threads a4 whereby a stronger some cases if preferred. The lock-nut O is made with an annular extension'or apron 02, which covers and conceals the threadsand prevents them from injury. Longitudinally on the stock A are inscribed a setof graduations a having intervals corresponding to the pitch of the thread a* on which the adjustmg-nut turns. With these graduations coperate'a series of circular graduations m on the beveled edge of the Calibrating sleeve: M. According to my construction this sleeve' is formed separately from the adjusting-nul K and adjustably secured thereto by-engag ing threads k3, m2 n the two members; while to hold the calibrating-nut M in any K fixed position on the nut K I provide the lock-nut N, the internal threads n' of which engage the threads m2 (Fig-2). I prefer also to provide the nut N with an annular extension or apron n2 which covers and pro tects the thread m2 of the'sleeve M. By-

means of the Calibrating-sleeve and locknut the reamer can be set at zero or anydesired cutting diameter. This is particularly advantageous in enabling the reamer to be ad-f justed-and readjusted repeatedly to compensate the wear of the cutterblades, so that the reading of the micrometer-graduations shall always be correct. It entirely climinates corrections for graduations, calculations and approximations in setting. After the blades are set in place 'and ground up to even diameter, the sleeve M will be set to zero and locked-up, and this will be ordiv narily done in the stock-room of the machine-shop and the reamer is then ready for great importance, because otherwise the bottom ofthe hole cannot be reamed4 trueV and Sjquare.'

VQl`a'n'd'g22, the cutter-bladeC is shown withuse by the machinists, who set it by means of.

the graduation to any desired cutting-diameter. The machinist therefore will confine his adjustmentto the nut K, while the toolkeeper will conne his adjustment to the.I sleeve M. The turning-head P isl in this instance shown as a conical head to iit a drillchuck, attached to the end of thestock A by means of screw-threads 1.7. Any other form of turning-headl may be substituted. It is.` in thisA instance made separate from thefl stock A because of the small diameter of the reamer, andV to Aenable'the several nuts and sleeves to be assembled in lace. It will be noted that among other a vantages' this construction enables the lower. end of the cutter-head to be made substantially solid, there being only a small hole at the centerto admit the head ,of the screw G. This gives a rigid and unyielding support'or backing' for the ends of the cutter-blades, which is of nur@ alternative forms of rigs. 1e, 2o,

two parallel oblique edgesI c? and c?, the latter being formed midway for an additional core-block H', which has a conical-face h2 the same as theLface h of the block H, the block H beingnountedend to end with the block H. 'This arrangement is however desirable only in long cutter-blades andis unnecessary in the smaller sizes. -I- have also l"here shown aclamping-nutE having a iat'face eA instead of the internally 'coned face e( of the nut E'. With this -coacts the tlatabutment- 'edge c", replacing the undercut edge 0*. The vaction of the clamping-mitin drawing the blades C together is accomplished, though not quite so effectively, by this lat-faced nut, -because the pressure thereo-uponft-he blades', acting in opposition to the cone-face "of the sleeve D produces a couple tending to turn the lower end inwardly. YI have also here shown,ias a substitute for the side-pin F, a4 pin F inserted in the end of the nut (see Fig. 20) and lying between two cutterblades. The same object could of course be accomplished in many other ways, of which two only are here shown.

- The large-sizedt-u'bular reamer shown in Sheet 2' of. the drawings is intended more particularly for reaming'large bores, such as small Uas-engine cylinders, as a substitute for the lathe-boring tools now com mon use. As is well known it is very diiicult'or rather'impossible to bore a cylinder true with a boring-bar, because ofv Y ,the give or yield thereof. With this tool exactl O. Ay-separate description of thejsame is.` -not therefore needed. The cross-bar J 'in'.

the lirst form is however replaced by a special' constructiomtoxenable it to avoid inter- .,feringwith `the central mandrel, to,-wit,.a

pair of'w'in -pieces j which are mounted on the end oft e tubular core I, vextending-fradiall therefrom -so as toV engage under the 'annu ar llug 'o'n vthe .adjusting-nut c. Ac-

cording to the preferred construction the inner edge of each wing-piece j is provided with a tenen j which is mortised into a corresponding longitudinal slot in the corea' (see Figs.v 24:v und 25'). The end of the tenon as shown in Fig. 24 is slightl undercut, but may more simply be cut o shown in Fig. 29. The wingpieces will be put inwith a driving fit, so that they canjnot fall out of place even if the core should ..slp down below 4the top of the adjustingnut. Ofcourse Iemay use three or more of such wing-pieces (but this is unnecessary) and the device would work with but one only, but imperfectly. The stock is shown fiat, as

as provided with screw-threads i? at its upper end.- the same as the stock A; and the upper end may also be provided with trans' verse.- slots (L8, which threads and slots are for the. purpose of fixing the reamer nonrotatably to the mandrel, but as this feature is not herein claimed nor forms any essen-v tial part of'my invention, it is not further illustrated. It will be understood of course that the cross-bar J shown in the solid form Fig. l may also be usedinthe tubular form provided the mandrel is suitably slotted to ,allow it to pass through. y

` vThe arrangement ofthe reamer shown in Figs. and 31'is identical with Figs. 23 to 29, except'in size and in having the lower;

end of the cutter-head b out of flat within the projecting lower ends of the blades', and a recess `at boto receive the polygonal head glo ofl the screw gu, and in having the inner ends of the blades c 'extend all the way'to the axis; in these respectsbein'g identical with the reamer of Figs. 1 to 7.

f This reamermay. be used either with .a mandrel eut off short of the blades c or-slotted out to receive them, according to the use which gis to 'be made of the reamer, but I de not claim any'special manner of using the reamer -asa part of my'invention.`

Fiomthe above description it will be obvious to thoseskilled in the art that the principles of myimprovedreamer are of -fveryvarious application and that the construction may be modified in various ways .and some of the elements omitted, without departingfrom the scope of the'inventlpn. I' do not "therefore consider my invention further limited thanis defined withinthe `scope of my claims.

'For the sake of definition, reifer`- tokthe end of the reamer shown as the lower end 'in-the' drawings as the lower or forward i said bore being terminated at thelower end end, and the other as the upper onrear Aen d, without intending any limitation as to the po'sitionin which the reamer is or maybe -used vHavingl ,thus described my invention,

whatI claim as new and desire to secure by Lette'rsPatet is:v I 0 I 1. A Vmetal-cutting tool" comprising, in-

comloination, a'hody having-a central bore,

b-'y.rfna te rial .which is an integral part of the cutter-head and has a hole of smaller size than the bore in it',l a plurality of cutlter-blades mounted in said'body, a longitudinal moving core-piecexslidably `mounted.

in said bore and-*adapted to. expandv said blades when moved longitudinally, means for advancing said core-piece, and rotatable clamping-means turning in said hole at the end of said body and actinginopposition to said expanding mea-ns.

Y 2. 'A metal-cutting tool comprising,- in

: combinaticu, a' body divided intermediately` into two pieces, I,to wit, a stock and cutterlhead, said cutter-head having'a bore open at theY lower or forward end thereof, a plurality of cutter-blades set in said cutterhead and having oblique ends resting upon the portion of said cutter -head lying beyond the end of saidcentral boreand a vcore-piece slidable longitudinally in said bore and adapted to expand -said cutterblades. when moved longitudinally, said core-piece being-inserted through the open upper or rear end of said cutter-head.

4. In a metal-cuttingtool, a vcutter-head havin a central bore terminating short of the lower ori forward end thereof, a plurality of cutter-blades set in said cutterhead, and a core piece slidable longitudinally( in said bore and adapted to expand said cutter-blades when vmoved longitudinally, saidcore-piece being inserted through the open upper or rear -end of saidv cutterhead,.and said cutter-blades'being bounded at their lower ends by oblique outwardly and downwardly extending edges, which rest; on corresponding surfaces on t-he lower end of said cutter-head. i

. 5. A metal-cutting tool of the class described comprising, in combination, a body made in two pieces, to wit, a stock and a cutter-head united together by a joint; each of said members having a bore thereinopen at the united ends and terminating short of the free end; the free end of the cutter head being closed except for an aperture of i smallerdiameter. than said bore; a plurality v of cutter-blades set in said cutter-head, an expanding-core movable longitudinally in the bore of said cutter-head and adapted to expand said blades; a member moving longi- -tudinally. in the' bore of said st'ock and adapted to advance said core;4 and means mountedexternally on said stock for actuatingsaid last-named member. s

i 6. Inl a metal-cutting tool of the class deally in said cutter-head, the latter having an under-cut abutment for the upper or rear edgesof sa-id cutter-blades at its outer surface, and a' clamping-device slidably mounted in said bore and adapted to press scribed, a cutter-headhaving a central bore, Y plurality ofcutter-blades mounted radiflendwise against -said cutter-blades upon a -1 int at or near their` respective inner edges,-

t us ascting in'conjunction with said abutrnent of the cutterfhead to draw the lower ororward ends of said cutter-blades inwardly.v n a 7. In 'a metal-cutting tool of the class described, -a cutter-head hav-ing a central' bore,-

'20 their respective'inner edgesfthus acting in conjunction with said' abutment on the cutter-head to draw thslower or forward ends of said cutter-blades inwardly;

8. In a metal-cutting tool of the class described, a cutter-head having a central bore,

vaplurality of cutter-blades set radially' in slots in sa1d`cutter-headand having parallel obliquely outwardly and downwardly .ex

tending end-edges, the outer` parts v0f the" upper edges of said slots forming abutments forthef upper end edges of said cutter-blades, the lower edges of said Slots being parallel Ito the lower end-edges ofsaid-cutter-blades and forming rests therefor, a slidable corev3&5 piece mounted in the bore above said cutterblades, anda clamping-device mounted slidably in said bore and adaptedto press upon inwardly projecting parts of said cutterblades thereby acting to draw the lower ends of said cutter-blade's'toward the center.

9. In a metal-cutting tool-of the class described, a cutter-head having a central bore, a plurality of cutter-blades set radially in slots in said cutter-head and having parallel obliquely outwardly and downwardly extending end-edges, the outer parts of the 'upper edges of said slotsforming abutments for the upper end-edges of said cutterj blades, the lower edges of said slots being parallel to the lower end-edges of said cutter-blades and forming rests therefor, a core-piece slidably mounted in-,said bore and acting in connection withsaid abutmentedges of said slots to expand said cutter-A blades, and a clamping-device'mounted slidably in said bore and adapted to press upon i inwardly projecting parts of said cutter blades thereby acting to draw the lower ends of said cutter-blades toward the'fcenter.'

10. In a metal-cutting tool of the class described, a cutter-headI having 'a central bore terminating short of the lower end thereof, a plurality of cutter-blades set in .said cutter-head, a member forsetting said cutter-l 65 blade and a clamping-member slidable longicentral bore,

tudinally in said bore and adapted when advanced to draw said blades together andl clamp them in any position in which. they 11. In a metal-cutting tool of the class de:

scribed, a cutter-head having a central bore y terminating short of the lower end thereof and having a second bore ofvsmaller diameter extending from the 'end of said bore to 'I the lower end, a plurality of cutter-blades set in said cutterhead,aclamping-member slidable lngitudinally in said bore and Y adapted whenadvanced to clamp and draw said blades together, and means rotating in vsaid second bore and abutting on said shoulder for .advancing said clamping-member.

12. -In a metal-cutting tool of the class described, a cutter-head having a central bore terminating short ofthe lower endthereof, a pluralityv of cutter-blades set radially therein, a clamping-nut slidable in said bore and adapted to engage saidv cutter-blades and draw them together, and-a clamping-V screw forl operating said clamping-nut engaging the threads thereof and rotating in the end of said bore, said clamping-screw having a head extending through a hole in the lower end of said cutter-head forming means for rotating it.

^ `13. VIn a metal-cutting tool of the class dev'scribed, the combination of 'a cutter-head having a plurality of radial slots closed at both ends, radially movable cutter-blades set in said slots, said cutter-head having a a clamping-nut slidably mounted in said central bore and "adapted .to clamp said blades lin position, 'a clamping-screw engaging said nut to move it longitudinally, and a member removably set in the side of said clamping-nut and having a projecting part which extends into one of said slots whereby it is prevented from rotating.

14.- A metal-cutting tool .of the class described, comprising in combination, a body having a central bore, a plurality of' cutte-bladeslradiallyset in said body, a longitudinally moving core-piece in said borev adapted to expand said blades, an adjusting-nut turning on threads around the exterior f said body above said blades, one .or more laterally projecting elements longitudinally movable in one or more transverse slots in said body acting on the end of said core-piece land engaging with said nut whereby the latter operates vthe blades, a longitudinal'zero-line inscribed on said body below said nut and graduated in accordance with the pitch of the threads of said nut, a

plurality of circular graduationsinto which the lower edge of said nut is divided and adapted to be read upon said zero line, and a lock-nut engaging with a second set of threads'on said body above said adjustingnut and adapted to lock the latter.

15. In a metal-cuttingtool of the class de-` x scribed, the combination of acutter-head having a plurality ofv radial slots therein, a plurality /ofcutter-blades mounted 1n said slots and having oblique downwardly and outwardly extending upper edges, a gagesleeve having a conical'undercut'lower edge .'extendingover the ends 'of lsaid slots a'nd forming an abutmentand `guide for said cutting-blades in-itheir radial movement, and

an im-movably fixed` abutment. for the oppo- 'site ,end of said gage-sleeve.

-slots, .and having oblique downwardly and Aoutwardly extending upper' edges, and a sleeve surrounding the-upper-part of said( cutter-head and abutting atv oncend upon said shoulder and at the other end overlylng the ends of said slots and eonically' undercut to form a guide and abutment for said blades in their radialmovement. y

` 17. A -metal-cutting tool comprising, 1n

-.combinat'ion, a stockya plurality-of cutterblades mounted therein,'a. core-piece and blades in an obliquely forward longitudinal means carriedtliereby acting to expand said direction `when `moved forwardlongitudisaid ,core-piece.

nally, a threaded nut engaging threads on the .surface of said stoelgand means trans-A mi'tting the endwise movementof said nutto y ISA metal-'cutting tool :'com'prising, in

f combination, a stock,'apluralityyofjcutterf' blades blades mounted therein, -a core-piece and means carried thereby acting to -expand said. when moved longitudinally, a

' threaded nut .engaging threads' on .the sur- .l face of said stock, and a .transverse member passing through a slot'insaidl'tock and abutting on the end of saidferefpiece, 1sald nut' having an annulariterial flange-lug which engages theend of transverse meinben- 19. A metaLcutting tool comprising, in. combination, a stock, a plurality fcutterf blades mounted therein, a core piece, nieans f carried thereby acting to expand saidhlade's;

when moved longitudinally, a ithreadedfiadjusting-'nut engaging `threads on the surface of said stock,`\a transverse vmeinberpas'sing throughs a slot in s aid stock and abutting on the.` end of said core-piece, said nuthav- 'lng `an annular internal flange-lug which against the'endofsaid adjusting-nut.

'L engages the` ends of saidtransverse-mem--' ber, and a llock-mit engaging asecondseries of threads on said stock and abutting 20, In a metal-cuttingtool, the combina-- tion of a stock havingAthre ads,."acorepiece moving said core-piece longitudinally comprising an adjustingmut having threads engaging the' threads of said stock, a graduated line on the surface of said stock and parallel' to Athe axis thereof, a circularly graduated sleeve having a' screw-threaded connection, with said adjusting-nut, and means for locking said sleeve `fast to said nut.

21. In a metal-cutting tool, the combination o f a stock having threads, a core-piece mounted centrally therein, and means for meving said core-piece longitudinally comprising an adjusting-nut havingthreads engaging thejthreads of said stock, agradu- .ated vli-'ne onA the` surface of said stock and lparallel-,to the axis thereof, a` circularly graduated sleeve having a screw-threaded.

geonnection with-'said adjusting-nut adapting it to longitudinal as well ascii-cular setting with respect to saidline, and a lock-nut engagingkthe threads onl said sleeve and acting to 'lock said sleeve fastin position with respect to said adjusting-nut. f

22. In a'me'taLcuttingtool, -the combina- -tion ofa body, a plurality of cutter-blades mounted .radially thereon and having each one or more-oblique edges and 'also an undercut oblique edge, al core-piece having one or more conical surfaces engaging said oblique edges, means. for advancing said corepiece, a clamping-piece having undercut surfaces engaging said undercut edges, and means for advancing said clamping-piece -todraw said blades together.

' 23. In a metal-cutting tool, the 'combination of a stock, a slotted cutter-head, cut ter-blades radially set in the slots of said head and having edges c cut to a'certain definite degree'of-.obliquity and having vfurther oppositely sloping oblique 'edges c2 cut to a certain predetermined angle of obliquity, a core-piece having a conical face thereon having the same angle of Obliquity' no -as the edges o2, means for moving said corepiece in ana'xial direction, and a sleeve i'xed to said cutter-head in a` definite positionand having an edgeadjusted to abut against the edge c and limiting the length of the slots in which the cutter-'bladesV move."

24. In a" metalfcutting to ol, bination of a stock, a slotted'cutter-head, f cutter-blades radially setin the slots of said Ahead and having edges 0" ut toy a certain 'definite degree ofV Obliquity and having further oppositely sloping oblique ed I c2 cut to a certain predetermined ang e of obliquity, a. core-piece having a conical face thereon having 'the same-angle of Obliquity `as theggedges c2, a sleeve fixed to saidcutterhea'giiifa definite position and having an edgfdjusted to abut against the edge c.

monnted centrally therein, and means for passing through -a slotA in said stockI and i abiitting-againstl the end of said, coreepiece,

` tion of a stock, a slotted cutter-liead, cutter-A and an adjusting-nut engaging with threads on said stock and having ineans engaging the en ds of said transverse member.

25. In a metal-cutting tool, the combinaah edge. adjusted to abut against the edge c4 fendflliitihealengthabfwthe slots inwhich Y' the cutter-blades move',A Said 4cutter-blades `having undercut, oblique edges c4, a clamping-nut. having an undercut obliqu'eJ surface e Yengaging said edges cl, and means for ad-.

vancing said 'clamping-nut to clamp the blades in adjusted position.

v26. In a metal-cutting tool, the combination of a stock, a slotted cutter-head, cutterblades radially set in the slots of said head and having edges c cut to a certain deinite Vvdegree of Obliquity and having further oppositely sloping oblique edges 62 lcut to a .certain predetermined angle of obliqiiity, a

cgrepiece having a conical face thereon haviii'gthe same angle ofobliquity as the edges c2, means for moving said core-piece in an axial direction, a sleeve fixedV to said cutter-head in a .definite position Valid havingan edge adjusted to abut against. th'e edge c and limit the length of the slots in vWhiclrthe cutter-blades move, said "cutter-blades having undercut oblique edges ct, a clamping-nut having an undercut oblique surface engaging said edges c4, and a clamping-screw turning in a socket iiimtliemend of said Ycutterheadand engaging said clamping-nut.

27. A metal-cutting tool comprising, in combination, astock having. two setsv of screwthread'son its exterior surface, a slot-- ted cutter-head on-the end of said stock, cut-V ter-blades mounted in the slots of said cutterheadand having oblique inner edges c2 and undercut oblique edges c4, Va 'core-piece hav-- ing one or more conical faces acting against the edges 02, a clamping-nut having an ob-,'

lique undercut surface engaging the under-Y cut edges c", a screw engaging said nut and rotating in the end of said cutter-headand prevented from endwisemovement, an iadj'usting-nut engaging. one set otthreads on.

said stoglg, aloek-nutengagingtheother set, and an Noperative connection between said adjusinglnut andl core-piece whereby the vlatter is moved longitudinally.

28. A metal-cutting tool comprising, in combinatioma stock having YtwoV setsA of screw-threads. on its exterior surface, a

slotted cutter-head on one end of said stock, cutter-blades mounted in the slotsl of said cutter-head and having oblique inner edges c2' and undercut oblique edges c4, a corepiece having one or more conical faces .act ing against the edges c2, a clamping-nut having an oblique undercut surface engaging the undercut edges c4, a screw engaging said nut 4 and rotating in the end of saidy cutter-head y and prevented from endwise movement, an adjiistinLggenut engaging' one set of threads on said stock, a lock-nut engaging the other set, an operative connection between said l adjusting-nut and core-piece whereby the latter is moved longitudinally', a circularly 80 graduated sleeve having an adjustable cnam gagement with said adjusting-nut;and

nieansfor 'lobliiigsidsleeve iii` its adjust-2 ed position. r L

29. In .an'eioansion metaLcut-ting tool, the combination O a radially slotted cutter-head, a plurality of cutting-blades set radially thereinheach cutter-blade havingits end-edges oblique downwardly and outwardly and parallel to each other, said cutter-head having surfaces coacting with and guiding said end-edges, the lower ends of said cutting-blades extending-beyond the endV of said cutter-head whereby to ream a. hole square at the bottom, and means for expanding and contracting said cutter-blades in an .obliquely longitudinal direction? 30. A metal-cutting tool of the class described comprising a tubular body having a central bore, a rplurality of cutter-blades set therein and `a tubular core for expanding said blades the whole toolfbeing tubular permitting the passage completely through it of a central mandrel.

31.*A Vrngtal-ci itting:tvo-ol of de- 1057 scribed... comprising in combination a tubular body, a plurality of cutter-blades set therein, a tubular core mounted concentrically within lsaid body and adapted to expand' said blades, and tubular clamping 110 means for-securing-said blades in adjusted position. p

32. A. metal-cutting tool of the class described comprising, in combination, a tubii! lar body, a plurality of cutter-bladesset therein, a tubular core mounted concentri-l vcally within said body and adapted to expand said blades, andan adjusting-nutl engaging threads on said "body and acting on said core. l

33. A metahcutting tool of the class described comprising, in. combination, a tubular body, a' plurality of cutter-blades set therein; a tubular core mounted concentrically within said body and adaptedwtoex pand .said blades, an adjusting-nut engagingzthreads on .said body and adapted to actuate said core, 'and a tubular clampingnut acting in o position to said adjustingnut, the tool as a whole being tubular.

34;'. A metal-cutting`,tool of the classde# lscribedcomprising, in combination, a completely .tubular body,.a` plurality of cutter# blades radially set therein, and completely tubular means' for, adjusting saidv blades mounted concentrically Withinsaid body.

85. A metal-cuttingtool 4of the class de-A u slcribedjcomprising, in combination, a-tubu- Y lar body having `a plurality of radial slots, a

plurality of cutter-blades set in the respective slots, means within saidl body forradjjusting theposition of said'blades andl means Within said body for, clamping said blades in adjusted position.; the whole tool y being tubular to permit the mountingof the 'same upon a fmandrel passing through'the center.l j

` 36. Ina metal-cutting tool of the class described, the combination of a tubular body having radial slots, a plurality ofcutterblades set in said slots, an adjusting-nut surrounding 'said body and engaging threads thereon, and means'within said body adapted to expand said cutter-blades and actuated vby said nut through one or more latcral orifices in said body; the, tool as a wholeheing concentrically tubular' permitting the mounting of the same upon a mandrel passing through the centen.

'37. A metal-cuttingtool offthe class described comprising, in combination, a tubular body `having .a plurality of radial slots., a plurality of cutter-blades set'in-said slots, said body having a central bore, a longitudinally movable tubularV core-piece mounted in s aid'boreand adapted to. act vnon 'said l Vthe center.4v 5o- Vblades to expand them, an adjusting-nut,` surrounding -said body and engagingA `threads thereon, and one or-m'ore-laterally projecting ,elements` connected with said-` core-pieec and longitudinally movable there with in one or more slots in said body, said projecting element or elements engaging with said nutthereby transmitting the longitudinal movement of said nut `to said coreb'eing tubular permitting themounting of the same upon a mandrel passing through' "38.A A metal-cuttingtool ot the class described, comprising, in combination, a tubui -lar body having `a centralbore and a4 plu rality ofiadial` slots, a plurality of cutterblades set 'in said slots, *a longitudinally movable tubular core-piece mounted in said bore andl adapted to act upon said blades to expand them, an adjusting-nut` lsurrounding'said body and engaging threads thereon.'` one' `or more laterally projecting elements connected 'Wit/h said `core-'piece and longi f tudinally movable therewith in one or more .slots in said body, said projecting element l es or elements. engaging with said nut thereby' transmitting the 'longitudinal movement of said nut to said core-piece and said blades,

' and a' tubular clamping-device mounted in said bore at thelower end of said blades and 'tool'as a Whole being tubular.

39.A7'metal'cutting tool of the.' class described comprising, in combination, a tubular body having a central bore and a plurality of radial slots, a plurality of cutterbladesmset in said slots', a longitudinally movable tubular core-piece mounted in said nutin said bore at .the lower end of said clamping-screw inthe end of said bore engaging the-'threads of said clamping-nut and. having a head extending through the lower tubular. 40. In a'tool, the combination of a stock having external threads,a core-piece mountsaid core-piece longitudinally comprising an adjusting nut having a set ot' internal threads 'engaging'the external threads on ,thel stock and 'having one end' bored out larger than the diameter o`f said threads and also-threaded internally, a circularly graduatedfsleeve having a set of external threads on one end Which-'extends Within the recessed end of said adjusting nut and engages the internal threads thereof, and means for locking said sleeve fast to said nut.

414111 alt'ool, the combination of a stock having external threads, a core-piece mounted' centrally therein, arid means for moving said 'core-piece longitudinally comprising an adjusting nut having a set of internal threads engaging the external threads on the 'stock and. having one end bored out larger vthan the-diameter of said threads and-also threaded internally, a circularly graduated sleeve having a'set 'of external threads on end of saidA adjusting nut and engages the internal threads thereof, and a lock-nut comprising an internally threaded ring also engaging the threads of said sleeve and adapted-to lock the same. in osition by jamming against the lendof tie, 'recessed portion of said nut. 'Y

having external threads, a longitudinally adjustable part thereof'and means for longitudinally adjusting said part Comprising acting in opposition to `said corefpiece; the

longitudinally movable tubular clampingblades .acting in opposition to said corc' piece 'to clamp said blades, and a tubular end of said body; the tool asa Whole being' .one end which extends within the recessed ed centrally therein, and means for moving 42. In a tool, in combination With a stock bore and adapted to actfupon said blades .to' 75 an adjusting nut having an operative connection with said part and having a'set of, internal` threads j engaging said external threads on the stock, said nut havin further one end recessed to a diameter arger than the diameter of said threads and also internally threaded, a longitudinal zero line on the surface of said-stock, a sleeve one end of which is circularly graduated,v

and adapted to be read by'its position with respect to said line and the other end of 'which is reduced to extend Within the recessed end of said nut and externally threaded toengage the threads of said'recessed end, said sleeve being provided midequal' to that of said nut and abutting 20 I against vthe recessed end thereof and having internal. threads engaging' that portion of `the threads of said sleeve'vvhich extend beyond therecessed end of said nut.

Inwitness whereof I have hereunto set.25

my hand this 7th`day of-February, 1908.

Witnesses: l

E. C. luaglaRLnIlv,v W. G. TRUErrNER.

HENRY lALTI-IER.I 

